﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace on
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("输入第一个数字");
            int a = Convert.ToInt32(Console.ReadLine());

            Console.WriteLine("请输入一个符号");
            char str = Convert.ToChar(Console.ReadLine());
            Console.WriteLine("输入第二个数字");
            int b = Convert.ToInt32(Console.ReadLine());
            switch (str)
            {
                case '+':
                    Console.WriteLine("两大数相加结果是{0}", a + b);
                    break;
                case '-':
                    Console.WriteLine("两大数相减结果是{0}", a - b);
                    break;
                case '*':
                    Console.WriteLine("两数相乘的结果是{0}", a * b);
                    break;
                case '/':
                    Console.WriteLine("两数相除的结果是{0}", a / b);
                    break;
                default:
                    Console.WriteLine("请输入一个正确的符号");
                    break;
            }
        }
    }
}